Are you on plasma 6.6?

Also “The metrics also show that basically no one is testing or developing Plasma on X11 anymore. The platform was already, for all intents and purposes, abandoned by KDE contributors.” There just isn’t the man power to keep supporting it

I’ve been using migadu for a few years. They’re a small company based out of Switzerland for their privacy laws. I haven’t had any issues with them. The base plan is cheap and has unlimited mailboxes. Their support is responsive. I’d recommend checking them out